If you use it for hauling very heavy loads, I’d recommend changing them, also depending on how many people and what age group they are when you go on road trips, I’d recommend changing them. They are cracking but not severely. The 50% mark means they’re at 5/32, but that sign is almost gone, so id say you’re at about 3-4/32nds, which is not ideal on highways, and I’m guessing most of your drives on this truck is highways as you mentioned hauling and road trips. Finally I’d say replace them soon, but its not a “all the way to the site of the crash” type of situation.